Rheumatoid arthritis（RA）is a common form of inflammatory arthritis leading to progressive bone and joint destruction. Because RA patients with progressive bone destruction experience an accelerated decrease in their quality of life, inhibition of disease progression and bone destruction has become an important clinical goal. Bone-related cells and inflammatory cytokines such as TNF-α and Interleukin-6（IL-6）are closely involved in bone destruction, and bone destruction is suppressed by drug intervention targeting these proinflammatory cytokines. In particular, recent studies have reported that the intervention of tocilizumab, an anti-IL-6 receptor antibody, results in bone repair in addition to suppression of bone and joint destruction, and these results suggest the potential for new therapeutic goals. Regarding the relationship between IL-6 and bone, many studies on osteoclasts have been published over many years; however, more recent studies have explored the relationship of IL-6 with osteoblasts and osteocytes. This review summarizes the relationship between IL-6 and bone-related cells from the perspective of clinical research and basic research such as in vitro and in vivo studies, and the possibility of IL-6 signal blockade in RA treatment.

Biologics have revolutionized the treatment of rheumatoid arthritis（RA）, with JAK inhibitors making their therapeutic effects possible through oral administration. The ORAL Surveillance trial, which directly compared JAK inhibitors with TNF inhibitors, did not demonstrate non-inferiority of JAK inhibitors. The interpretation of this study is complicated by the fact that TNF inhibitors have been reported to be effective in reducing the incidence of these events in RA patients. The results illustrate the importance of screening to the extent possible at the time of introduction of molecular-targeted therapies. Herpes zoster（HZ）is an adverse event that has received new attention with the JAK inhibitor trials. However, HZ has been known to be increased in RA patients for some time, and JAK inhibitors increase the frequency of HZ 2- to 3-fold, and the incidence in Japan is 2-fold higher from rest of the world. The proactive prophylaxis with Shingrix, a subunit vaccine, should be taken. In consideration of cost and expense for screening and vaccination, countermeasures against adverse events of molecular-targeted therapy is closely related to the fundamental issue of shared-decision making.

Objective　To evaluate usefulness of remission criteria of SLE.

Methods　Medical record of eighty-three Japanese SLE patients were reviewed. Lupus Low Disease Activity State（LLDAS）was defined as SLEDAI ≦4 and prednisolone（PSL）≦7.5mg/day. Definitions of Remission in SLE（DORIS）included patients with clinical and complete remission, clinical remission on treatment（ROT）, and complete ROT.

Results　All remissions（DORIS）had LLDAS, and 78.4% of LLDAS had remission. At enrollment, 61.4% had LLDAS; 22.9%, clinical ROT; and 25.3%, complete ROT. Two patients with clinical remission（1.4%）had a relapse, but no patients with complete remission had no relapse. The flare occurred in 69.9% of 79 clinical ROT and 45.7% of 35 complete ROT. Patients who achieved LLDAS in more than half of observation period or DORIS remissions significantly received 2.5mg/day of PSL, had fewer instances of nephropathy and lower SLICC/ACR damage index（SDI）than those with LLDAS < 50% or without remission. The multivariate analysis showed that flares and renal involvement were risk factors, but PSL 2.5mg/day was protective against damage accrual. Patients taking PSL 2.5mg/day had significantly less relapses and lower SDI than patients taking PSL 5 to 7.5mg/day. The present study demonstrated that the best therapeutic strategy would be firstly achieving LLDAS with PSL ≦7.5mg/day, followed by clinical or complete ROT with PSL ≦5mg/day, and finally clinical or complete ROT with PSL 2.5mg/day. Corticosteroid-off remission should be avoided in terms of preventing flares.

Conclusion　LLDAS and DORIS remissions tightly overlap each other. LLDAS may be a useful indicator of remission, and DORIS will be valuable to evaluate the degree of achieved remission.

Objectives: To identify risk factors associated with renal dysfunction and difference between serum cystatin C（Cys-eGFR）and creatine（Cr-eGFR）in estimating glomerular filtration rate in patients with rheumatoid arthritis（RA）. Methods: 359 patients with RA were enrolled in this study. The risk factor associated with renal dysfunction was analyzed using Cys-eGFR for one year. The difference between levels of Cys-eGFR and Cr-eGFR at baseline was used for analysis.

Results: The risk factor associated with the deterioration of renal dysfunction was disease activity（odds ratio, 1.76; 95% confidence interval, 1.05-2.96）in patients under 60 years old. When comparing levels of Cys-eGFR and Cr-eGFR, Cr-eGFR was significantly greater in patients 80 and older years old（P = 0.034）and significantly lower in patients under 60 years old（P < 0.001）.

Conclusions: In RA patients under 60 years, it is important to control the disease activity for preventing the renal dysfunction. Use of Cys-eGFR might be more appropriate for the management of renal function in elderly patients with RA.

Objective: The aim of this study was to investigate the influence of coronavirus disease 2019（COVID-19）on the patients referred to our hospital.

Methods: The clinical data of the patients who were referred to our hospital between January 2018 and March 2021 were retrospectively collected and compared between before the pandemic（from January 2018 to February 2020）and after the pandemic（from March 2020）.

Results: The average number of referred patients significantly decreased from 0.98/day（before the pandemic）to 0.53/day（after the pandemic）. The rate of the referrals for the purpose of surgery did not change between before and after the pandemic, however, the patients referred for surgery of large joints in lower limbs significantly increased from 34.6% to 56.0%（p=0.03）. On the other hand, the rate of the patients for surgery of upper limbs significantly decreased from 38.5% to 12.0%（p=0.01）. The details of medical treatment introduced in our hospital did not show any changes between before and after the pandemic.

Conclusion: The number of the referred patients decreased after the pandemic, suggesting that the patients who were afraid of spreading of COVID-19 refrained from visiting local clinics. Surgeries for large joints in lower limbs were performed the same as before pandemic, on the other hand, surgeries for upper limbs were significantly decreased because upper limb surgery can be postponed relatively easily. There was no change in drug treatment before and after the pandemic, which means the adequate treatment was performed in the same manner as before pandemic.

The patient was a 22-year-old man with a history of persistent fever since August 20XX, and subsequent polyarthritis. The patient consulted a local physician who prescribed antibiotics, which did not improve his symptoms. He was referred to our department 12 days after his fever started. Blood test revealed a mildly low white blood cell count of 3,300/μL. Rheumatoid factors, anti-cyclic citrullinated peptide antibodies, and antinuclear antibodies were not elevated. Epstein Barr Virus antibody test revealed that the patient was previously infected, he tested negative for human immunodeficiency virus antibodies, parvovirus B19 antibodies, and cytomegalovirus C7-HRP. Physiological findings included bilateral ankle joint inflammation. Synovial fluid collected from his right ankle joint revealed a cell count of 25,300/μL, which is in accordance with inflammatory synovial fluid. Histiocytes comprised 88% of the cells. Enlarged lymph nodes were also found in the right axilla. He was diagnosed with Kikuchi-Fujimoto disease（KFD）based on lymph node biopsy of the same site. There are previous studies of KFD complicated with joint inflammation; however, synovial fluid findings have not been reported. Histiocyte-dominant synovial fluid is consistent with one of the disease conditions of KFD. Arthrocentesis is easy to perform and may provide knowledge on the characteristics of synovial fluid that help in diagnosing KFD. Future studies should include more cases of KFD with arthritis.

LPS plays an important role in the establishment of inflammation. LPS binds to LPS binding protein（LBP）, and CD14 further binds to LPS/LBP complex to induce inflammatory signals into the cell. This study examined the relationship between serum LBP levels and ACPA antibodies in long-term（> 5 years）patients with rheumatoid arthritis. To evaluate the clinical significance of LBP as a biomarker, CRP and IL-6, which are indicators of inflammation, were simultaneously measured.

In this study, the LBP（Mean±SD）of healthy subjects, the OA group, and the RA group was measured. The measurement results of LBP were 3.7±1.3μg/mL for healthy subjects, 6.1±2.4μg/mL in the OA group, and 11.1±5.2μg/mL in the RA group, which were the highest values in the RA group with statistical significance.

Furthermore, LBP tended to increase as the stage and class progressed. In addition, a correlation（r=0.410）was observed with ACPA, and the ACPA positive cases demonstrated significantly（p < 0.002）higher LBP concentration in comparison with the ACPA negative cases.

Therefore, the measurement of high-sensitivity LBP may be one of the indicators for new pathological analysis of RA.

Objective: To evaluate long-term outcomes and multi-slice computed tomography（MSCT）-measured chronological remaining normal lung volume in patients with interstitial lung disease（ILD）having the anti-aminoacyl tRNA synthetase（ARS）or the anti-melanoma differentiation-associated gene 5（MDA5）antibodies.

Methods: We retrospectively investigated 51 ILD patients with anti-ARS（n = 38）or anti-MDA5（n = 13）between January 2014 and May 2019. Patients were classified as having polymyositis/dermatomyositis（PM/DM）, clinically amyopathic DM（CADM）, or interstitial pneumonia with autoimmune features. The MSCT-based chronological remaining lung volumes were measured.

Results: A total of 29%, 45%, and 5%, and 0%, 31%, and 54% of patients with anti-ARS and anti-MDA5 had PM/DM/CADM, respectively. The MSCT-measured mean（SD）remaining lung volumes at baseline were 3100（720）mL and 2796（887）mL in the anti-ARS and anti-MDA5 groups, respectively（P = 0.226）. Survival was more favorable in patients with anti-ARS than in those with anti-MDA5（93% vs. 77% at 4-year, P = 0.022）. Remission was achieved in 94% and 85% of patients with anti-ARS and anti-MDA5, respectively, who received induction therapy. The remaining lung volumes did not significantly increase over time [mean（SD）, 21（9）months] in the anti-ARS group（P = 0.867）but improved in the anti-MDA5 group（P = 0.030）. The mean（SD）annual percent change was 104（18）% vs. 119（15）% in anti-ARS-positive vs. anti-MDA5-positive patients（P = 0.055）.

Conclusion: Despite the favorable survival of anti-ARS-positive patients, ILD improvement was minimal. Long-term therapeutic strategies for ILD in this subset of patients are warranted.

  Pain catastrophizing is defined as an exaggerated negative orientation toward pain, and an increased number of pain sites is associated with increased pain catastrophizing. In this study, the pain catastrophizing scale（PCS）was applied to 204 outpatients with rheumatoid arthritis（RA）in our hospital. Multiple regression analysis was performed to identify the key factors that influence pain catastrophizing using the PCS scores as the objective variables and age, sex, physical activity, visual analogue scale（VAS）scores, annual radiographic progression using the modified Sharp van der Heijde score（S-H method）, and treatment drugs as the independent variables. The mean total pain catastrophizing score was 18.8±12.2. The subscale scores were as follows: rumination, 9.4 ± 5.8; helplessness, 4.3 ± 3.1; and magnification, 5.1 ± 4.3. The scores for rumination and magnification were high in RA. Rumination was significantly associated with joint swelling（p=0.029）, magnification was significantly associated with annual radiographic progression per the S-H method（p=0.049）, and helplessness was significantly associated with VAS scores（p=0.019）. According to the fear avoidance model, fear of pain and excessive avoidance of behaviors associated with pain lead to depression and adjustment disorder, thereby resulting in a vicious cycle of chronic pain. Nurses caring for RA should make efforts to reduce the psychological fear in RA patients they encounter during their practice.